Air washers have been used extensively in treating moving air streams routed through industrial air conditioning systems which are designed to maintain relatively high moisture levels in the conditioned space. The water spray introduced by these air washers results in water droplets being entrained by the moving air streams. In order to remove these water droplets, moisture eliminators are generally used in conjunction with air washers to ensure that substantially all of the water carried by the air is in the vapor state.
Moisture eliminators are typically constructed of a series of cooperating partitions which are positioned in a spaced, parallel relationship. The partitions are usually provided with an undulated configuration to impart a zigzag movement to the air stream passing between the spaced partitions. Moisture eliminators of this type are shown, for example, in U.S. Pat. Nos. 3,338,035 and 3,912,471. The effectiveness of an eliminator in removing water droplets from an air stream is largely determined by the design of the eliminator and the velocity of the air stream passing through it. Thus, an eliminator can be specifically designed for a high velocity air stream and it will function satisfactorily as long as the air velocity is maintained within a certain range. When the air velocity falls appreciably below this range, there is a corresponding reduction in the eliminator's effectiveness in removing water droplets from the air stream. Such a situation arises, for example, in systems that employ a bypass arrangement for routing a portion of the return air from the conditioned zone around the air washer. As the proportion of air bypassing the air washer increases, the velocity of the air moving through the air washer and the eliminator decreases and eventually reaches a velocity that is unsuitable for removal of entrained water droplets by the eliminator.
In recent years energy considerations have led to the development of variable air volume (hereinafter VAV) systems for processing and distributing conditioned air. In a manner analogous to that discussed above for bypass arrangements, air washers and moisture eliminators used in VAV systems also lead to water droplet carryover as the volume of air being moved through the eliminator and the resultant air velocity associated therewith fall below levels at which the eliminator operates effectively. Accordingly, VAV systems employing an air washer and eliminator arrangement have been limited to operation within a relatively narrow range of air volumes.